Guanosine tetra- and pentaphosphate ((p)ppGpp) molecules are one of the key players in the stress response of bacteria. Accumulation of these alarmones activates the stringent response, usually triggered by different nutritional stresses. For Pseudomonas putida, there is only limited data available on the importance of the stringent response in stress situations. In this project we tested systematically how stringent response affects Pseudomonas putida and how it contributes to bacteriophage tolerance. We analysed the proteomes of Pseudomonas putida PaW85 (wild type; wt) and its ppGpp deficient strain (ΔrelAΔspoT; dRS) in LB, and M9 minimal media with glucose or succinate as sole carbon sources.